Abstracted the Retry Policy logic to allow for custom policies.
Reduced threads and memory used by cassandra instances in travis.
Merge pull request #247 from phillipCouto/reduce_travis_resources

Reduced threads and memory used by cassandra instances in travis.
Merge remote-tracking branch 'upstream/master' into abstract_retries
Updated godocs at an attempt to improve understanding of said documentation.
Fixed spelling error.
Merge pull request #246 from phillipCouto/abstract_retries

Abstracted the Retry Policy logic to allow for custom policies.